Ultrasonic irradiating device



Feb. 13, 1962 c. M. VAN DER BURGT ,0 20

ULTRASONIC IRRADIATING DEVICE Filed Feb. 16, 1959 2 Sheets-Sheet 1LIQUID SOURCE LIQUID STORAGE INVENTOR CORNELIS M. VAN DER BURGT BY f-=--....2.

AGE

Feb. 13, 1962 c. M. VAN DER BURGT 3,021,120

ULTRASONIC IRRADIATING DEVICE Filed Feb. 16, 1959 2 Sheets-Sheet 2 FIG.3

INVENTOR GORNELIS VAN DER BURGT four segments.

3,@Zl,l2 Patented Feb. 13, 1962 3,021,120 ULTRASONIC DIA'IING DEVICECornelis Martinus van der Burgt, Einrlhoven, Netherlands, assignor toNorth American Philips Company,

Inc., New York, N.Y., a corporation of Delaware Filed Feb. 16, 1959,Ser. No. 793,565 Claims priority, application Netherlands Feb. 20, 1958Claims. (til. 25972) The present invention relates to an ultrasonicirradiating device. More particularly, the invention relates to anultrasonic irradiating device of the type described in copending UnitedStates patent application Serial No. 785,- 830, filed January 9, 1959.

In the ultrasonic irradiating device of the type of the presentinvention, the ferrite ring and the core and primary winding of thetransformer are wholly surrounded by the extension of the wall of thevessel, so that said parts are housed in a space which is fully closed.

The present invention constitutes an improvement over the devicedescribed in said copending application.

According to the present invention, at least part of the extension ofthe wall of the vessel is constituted by one and preferably tWo or moreindividual current conductors.

The device of the present invention, which is formed as an integralunit, is simple and compact due to the absence of a separate secondarywinding on the ferrite ring and has a very high electroacousticefficiency.

A In order that the invention may be readily carried into effect, itwill now be described with reference to the accompanying drawings,wherein:

FIG. 1 is a longitudinal section of the ultrasonic irradiating device ofthe type of the present invention;

FIG. 2is a pair of cross-sections taken along the lines IIII of FIG. 1,modified to illustrate another embodiment of the device of the presentinvention; and

FIG. 3 is a pair of cross-sections taken along the lines IIII of FIG. 1,modified to illustate still another embodiment of the device of thepresent invention.

An ultrasonic irradiating device of the type of the present inventioncomprises a vessel 1 which is set into vibration in radial directionsfor the ultrasonic treatment of liquids or matter in liquids. The wallof the vessel 1 may be of piezomagnetic or magnetostrictive material.The wall is surrounded by at least one piezomagnetic ferrite ring 2 and/or 3 which, in turn, is surrounded by an extension 8 of the wall of thevessel 1 at one end of said vessel. Each of the ferrite rings 2 and 3comprises Thin ferromagnetic discs 4, comprising, for example,Ferroxdur, are positioned between the segments of the ferrite rings 2and 3. The discs 4 are magnetized in the direction of the arrows, forthe purpose of pie-polarization. The extension of the wall surrounds thecore 5 of the supply transformer with the primary winding 6 and isconnected to the other end 9, 10 of the vessel, thereby forming a singleclosed secondary winding of which the wall of the vessel forms part. Aliquid, preferably degassed, is provided in the space 12 between theWall of the vessel and the ferrite ring as a medium for transmitting thevibration from said rings to said vessel. The primary winding 6comprises two parts and is connected to an electrical energy generator 7operating at an ultrasonic frequency. The rings 2 and 3 are resilientlysuspended in the cylindrical extension 8 in liquidtight sponge rubber orsponge plastic rings 11. Reference numerals 13 and 14 indicate a sealingplate and a sealing rings for the liquid in the space 12. The plate 13and rings 14 consist of electric insulating material.

The rings 2 and 3 are set into vibration in radial directions by themagnetic field produced by the cylindrical extension 8 which acts as thesecondary winding of the transformer by cutting the magnetic fieldproduced by the primary winding 6 of said transformer. Since the rings 2and 3 are piezomagnetic ferrites they vibrate or are displacedphysically under the influence of the magnetic field provided by thecylindrical extension 8. The vibration is transmitted via the liquids inthe space 12 to the vessel 1 which contains either the liquid to betreated or the object to be treated, immersed in liquid. No vibrationenergy is lost in an outward radial direction due to the insulatingaction of the rings 11. If the portion 10 is in the form of a tube, asshown, a continuous flow of liquid can be treated, provided the upperside of the vessel 1 is provided with a supply tube.

The term ultrasonic is to be understood in this case to mean alsoaudible frequencies upwards of 10 kilocycles per second.

In accordance with the present invention, the cylindrical extension 8 ofFIGS. 1 and 2 is in the form of strips or segments. In FIG. 3 accordingto the invention the current conductors consist of four strips 8 orflexible cables which may be arranged in a simple manner, moreparticularly symmetrically around the vessel 1.

The current conductors 8 may extend with respect to the wall of thevessel in radial directions or in more or less tangential directions, sothat the portions of the secondary winding, formed by the cylindricalextension, not belonging to the wall of the vessel may fundamentallyhave the shape of, for example, a birds cage.

Since the surrounding outer portion 8 of the secondary winding, formedby the cylindrical extension, is not closed, the transformer is alsocooled more satisfactorily.

According to another feature of the invention, at least a portion of thecylindrical extension 8 consists of conductive gauze material asillustrated in the embodiment of FIG. 2, which fully surrounds theferrite ring and the core of the transformer, thus protecting saidparts.

Suitable ferrite materials for making the rings 2 and 3 of theultrasonic transducer, are well known and are described, for example, inthe article, Ferroxcube Material for Piezomagnetic Vibrators, by thepresent inventor, published in the Philips Technical Review, volume 18,No. 10, March, 1957, pages 285298. Suitable materials for the discs 4are disclosed, for example, in the publication Ferroxdure, a Class ofNew Permanent Magnet Materials by l. I. Went et al., Philips TechnicalReview, volume 13, No. 7, January 1952, pages 194- 208.

What is claimed is:

1. In an ultrasonic irradiating device comprising an electricallyconductive vessel adapted to hold a liquid, a piezomagnetic ferrite ringpositioned substantially coaxially around the said vessel, said ringbeing coupled to said vessel for transmitting vibration thereto, aprimary transformer winding and input means for electrical energygenerating means operating at an ultrasonic fre quency for energizingsaid primary winding, means for inducing piezomagnetic vibrations insaid ring comprising a secondary transformer winding, said secondarywinding comprising said vessel and an extending portion thereof andbeing positioned substantially surrounding said ring and in inductiveproximity to the said ring and to said primary winding, at least a partof said extending portion comprising at least a pair of currentconducting strips arranged symmetrically around said vessel.

2. In an ultrasonic irradiating device comprising an electricallyconductive vessel adapted to hold a liquid, a piezomagnetic ferrite ringpositioned substantially coaxially around the said vessel, said ringbeing coupled to said vessel for transmitting vibration thereto, aprimary transformer winding and input means for electrical energygenerating means operating at an ultrasonic frequency for energizingsaid primary winding, means inducing piezomagnetic vibrations in saidring comprising a secondary transformer winding, said secondary windingcomprising said vessel and an extending portion thereof and beingpositioned substantially surrounding said ring and in inductiveproximity to the said ring and to said primary winding, at least a partof said extending portion comprising at least a pair of currentconducting strips spaced apart and arranged symmetrically around saidvessel in substantially cage-like configuration and electricallyinterconnecting spaced portions of said vessel.

3. In an ultrasonic irradiating device comprising an electricallyconductive vessel adapted to hold a liquid, a piezomagnetic ferrite ringpositioned substantially coaxially around the said vessel, said ringbeing coupled to said vessel for transmitting vibrations thereto, aprimary trans-former winding and input means for electrical energygenerating means operating at an ultrasonic frequency for energizingsaid primary winding, means inducing piezomagnetic vibrationsin saidring comprising a secondary transformer winding, said secondary windingcomprising said vessel and an extending portion thereof and beingpositioned substantially surrounding said ring and in inductiveproximity to the said ring and to said primary winding, at least a partof said extending portion comprisin a conductive gauze materialsurrounding said ring and said primary Winding.

4. In an ultrasonic irradiating device comprising an electricallyconductive vessel adapted to hold a liquid, a

comprising a secondary transformer winding, said secondary windingcomprising said vessel and an extending portion thereof and beingpositioned substantially sur rounding said ring and in inductiveproximity to the said ring and to said primary winding, at least a partof said extendingportion comprising at least a pair of currentconducting strips arranged symmetrically around said vessel, andresilient material positioned between said ring and said extendingportion for suspending the said ring.

5. In an ultrasonic irradiating device comprising an electricallyconductive vessel of piezomagnetic material adapted to hold a liquid, apiezomagnetic tferrite ring positioned substantially coaxially aroundthe said vessel, fluid means between said vessel and said ring fortransmitting vibrations therebetween, a primary transformer winding andinput means for electrical energy generating means operating at anultrasonic frequency for enengizing said primary winding, means forinducing piezomagnetic vibrations'in said ring comprising a secondarytransformer winding, said secondary winding comprising said vessel andan extending portion thereof and being positioned substantiallysurrounding said ring and in inductive proximity to the said ring and tosaid primary Winding, at least a part of said extending portioncomprising at least a pair of current conducting strips arrangedsymmetrically around said vessel in substantially cage-likeconfiguration, and resilient material positioned between said ring andsaid extending portion for suspending the said ring.

References Cited in the file of this patent UNITED STATES PATENTS2,565,159 Williams Aug. 21, 1951 2,713,127 Harris July 12, 19552,761,077 Harris Aug. 28, 1956

